Generation and Culture of Neural Progenitor Cells using the STEMdiff Neural System

Generation and Culture of Neural Progenitor Cells using the STEMdiff Neural System

i Table of Contents 1.0 Introduction... 1 2.0 Materials, Reagents and Equipment... 2 2.1 Materials Required for Neural Induction Protocols...2 2.2 Materials Required for Neural Progenitor Cell Culture...2 2.3 Equipment...3 3.0 Important Parameters for Successful Neural Induction from Human ES and ips Cells... 4 4.0 Preparation of Reagents and Materials... 5 4.1 Matrices for Coating Cultureware...5 4.1.1 Poly-L-Ornithine/Laminin...5 4.1.2 Corning Matrigel...6 4.2 AggreWell 800 plates...6 5.0 Neural Induction: Generating NPCs from Human ES and ips Cells... 7 5.1 EB Protocol...8 5.2 Monolayer Culture Protocol... 13 6.0 Neural Progenitor Cell Culture... 15 6.1 Complete STEMdiff Neural Progenitor Medium... 15 6.2 Passaging Protocol... 16 6.3 Freezing Protocol... 16 6.4 Thawing Protocol... 17 7.0 Troubleshooting... 18 7.1 Generating NPCs Using the EB Protocol... 18 7.2 Generating NPCs Using the Monolayer Culture Protocol... 19 8.0 References... 20

1 1.0 Introduction Human pluripotent stem cells (hpscs), including human embryonic stem (ES) cells and induced pluripotent stem (ips) cells, are characterized by their ability to differentiate into tissues derived from any of the three embryonic germ layers. This includes endodermal tissues, such as intestine, pancreas or liver, mesodermal tissues, such as blood or cardiomyocytes, and ectodermal tissues, such as the nervous system or skin 1. Under specific conditions, human ES and ips cells can be directed to differentiate into neural progenitor cells (NPCs), which are characterized by their capacity to expand and generate the major differentiated cell types of the central nervous system (CNS): neurons, astrocytes and oligodendrocytes. NPCs can be generated either using a monolayer culture protocol or an embryoid body (EB) protocol. In this manual, we will describe these two protocols. We will also introduce the STEMdiff Neural System (Table 1) for hpsc-derived NPC research, which is a suite of products specifically designed for the generation, isolation, characterization, expansion and cryopreservation of hpsc-derived NPCs. All STEMdiff Neural System media are defined and serum-free. Table 1. The STEMdiff Neural System for hpsc-derived NPC Research APPLICATIONS PRODUCT NAME CATALOG # Generation of NPCs from hpscs STEMdiff Neural Induction Medium 05835/05839 Isolation of CNS-type NPCs STEMdiff Neural Rosette Selection Reagent 05832 Expansion of NPCs STEMdiff Neural Progenitor Medium 05833 Cryopreservation of NPCs STEMdiff Neural Progenitor Freezing Medium 05838 Characterization of NPCs STEMdiff Human Neural Progenitor Antibody Panel 69001

2 2.0 Materials, Reagents and Equipment 2.1 Materials Required for Neural Induction Protocols NEURAL INDUCTION PROTOCOL PRODUCT DESCRIPTION CATALOG # EB and Monolayer Culture STEMdiff Neural Induction Medium 05835/05839 EB and Monolayer Culture Gentle Cell Dissociation Reagent 07174 EB and Monolayer Culture DMEM/F-12 36254 EB and Monolayer Culture D-PBS (without Ca 2+ and Mg 2+ ) 37350 EB and Monolayer Culture Y-27632 (Dihydrochloride) 72302/72304 EB and Monolayer Culture Trypan Blue 07050 EB and Monolayer Culture Poly-L-Ornithine Sigma Catalog # P4957 EB and Monolayer Culture Laminin Sigma Catalog # L2020 EB and Monolayer Culture Corning Matrigel hesc-qualified Matrix Corning Catalog #354277 EB STEMdiff Neural Rosette Selection Reagent 05832 EB AggreWell 800 27865/27965 EB Large bore disposable 1 ml tips e.g. Rainin Catalog #HR-1000 WS EB 37 µm Reversible Strainer 27215/27250 2.2 Materials Required for Neural Progenitor Cell Culture PRODUCT DESCRIPTION CATALOG # STEMdiff Neural Progenitor Medium 05833 STEMdiff Neural Progenitor Freezing Medium 05838 DMEM/F-12 36254 ACCUTASE 07920 Trypan Blue 07050 Poly-L-Ornithine Sigma Catalog # P4957 Laminin Sigma Catalog # L2020 Corning Matrigel hesc-qualified Matrix Corning Catalog #354277

3 2.3 Equipment Vertical laminar flow hood certified for Level II handling of biological materials Incubator with humidity and gas control to maintain 37 C and 95% humidity in an atmosphere of 5% CO 2 in air Low speed centrifuge with a swinging bucket rotor (e.g. Beckman GS-6) with an adaptor for plate holders Pipette-aid with appropriate serological pipettes Hemacytometer Micropipette and serological pipettes with appropriate tips Inverted microscope Isopropanol freezing container -150 C freezer or liquid nitrogen (LN 2 ) vapor tank -80 C freezer -20 C freezer Refrigerator (2-8 C)

4 3.0 Important Parameters for Successful Neural Induction from Human ES and ips Cells High Quality Human ES and ips Cells It is critical to start with high quality human ES and ips cell cultures for efficient neural induction. Note: Refer to the Technical Manuals: Maintenance of Human Pluripotent Stem Cells in mtesr 1 (Document #29106) or TeSR -E8 (Document #29267) for complete instructions on culturing high quality ES and ips cells using these feeder-free maintenance media. These documents are available on our website at www.stemcell.com or contact us at techsupport@stemcell.com to request a copy. AggreWell 800 AggreWell 800 plates are recommended for generating hpsc-derived EBs for neural induction. These plates enable easy generation of uniformly-sized EBs, making differentiation experiments more reproducible. For efficient neural induction in STEMdiff Neural Induction Medium, it is recommended to generate EBs consisting of approximately 10,000 cells. Plating of EBs Intact EBs should be harvested from the AggreWell 800 plates and plated onto matrix-coated plates. Dissociation of EBs into small clusters or single cells can lead to cell death and therefore low NPC yield. It is important to avoid breaking up EBs before plating them onto matrix-coated plates. Choosing an Appropriate Matrix for Neural Induction Successful generation and maintenance of human NPCs requires the use of a suitable matrix to allow attachment of neural aggregates. Poly-L-ornithine/Laminin (Sigma Catalog # P4957 and # L2020, respectively) or Corning Matrigel hesc-qualified Matrix (Corning Catalog #354277) are recommended for use with the STEMdiff Neural System. Enrichment of CNS-Type NPCs In the EB protocol, neural rosette selection can be used to isolate CNS-type NPCs from a mixed culture of cells. Manual rosette selection is a laborious and time-consuming process. STEMdiff Neural Rosette Selection Reagent allows rapid and efficient isolation of neural rosettes, without harsh enzymatic treatment. ROCK Inhibitor The ROCK inhibitor Y-27632 (Dihydrochloride) has been reported to increase the survival of single hpscs and improve EB formation 2.

5 4.0 Preparation of Reagents and Materials 4.1 Matrices for Coating Cultureware 4.1.1 Poly-L-Ornithine/Laminin 1. Dilute poly-l-ornithine (PLO) solution in phosphate-buffered saline (PBS) to reach a final concentration of 15 µg/ml. 2. Add the diluted PLO solution to coat tissue culture-treated cultureware. See Table 2 for recommended coating volumes. Table 2. Recommended Volumes of Matrix for Coating Cultureware TISSUE-TREATED CULTUREWARE 24-well plate 12-well plate 6-well plate VOLUME OF DILUTED MATRIX 300 µl/well 500 µl/well 1 ml/well 100 mm dish 6 ml/dish T-25cm 2 flask T-75cm 2 flask 3 ml/flask 8 ml/flask 3. Swirl the cultureware to spread the PLO solution evenly across the surface. 4. Incubate at room temperature (15-25 C) for at least 2 hours or seal the cultureware (e.g. with Parafilm ) and incubate overnight at 2-8 C. Do not let the PLO solution evaporate. 5. Gently remove the PLO solution using a serological pipette or by aspiration. Ensure that the coated surface is not scratched. 6. Wash twice with PBS, followed by a third wash with DMEM/F-12. 7. Dilute laminin in DMEM/F-12 to reach a final concentration of 10 µg/ml. 8. Add the diluted laminin solution to PLO coated cultureware. See Table 2 for recommended coating volumes. 9. Incubate at room temperature (15-25 C) for at least 2 hours or seal the cultureware (e.g. with Parafilm ) and incubate overnight at 2-8 C. Do not let the laminin solution evaporate. Note: If not used immediately, the cultureware must be sealed to prevent evaporation of the laminin solution (e.g. with Parafilm ) and can be stored at 2-8 C for up to two weeks after coating. Allow stored coated cultureware to come to room temperature (15-25 C) for 30 minutes before plating cells.

6 4.1.2 Corning Matrigel Corning Matrigel hesc-qualified Matrix should be aliquoted and frozen. Consult the Certificate of Analysis supplied with the Corning Matrigel for the recommended aliquot size ( Dilution Factor ) to make up 24 ml of diluted matrix. Make sure to always keep Corning Matrigel on ice when thawing and handling to prevent it from gelling. 1. Thaw one aliquot of Corning Matrigel on ice. 2. Dispense 24 ml of cold DMEM/F-12 into a 50 ml conical tube and keep on ice. 3. Add thawed Corning Matrigel to the cold DMEM/F-12 in the 50 ml tube and mix well. The vial may be washed with cold medium if desired. 4. Use the diluted Corning Matrigel solution immediately to coat tissue culture-treated cultureware. See Table 2 for recommended coating volumes. 5. Swirl the cultureware to spread the Corning Matrigel solution evenly across the surface. 6. Incubate at room temperature (15-25 C) for at least 1 hour before use. Do not let the Corning Matrigel solution evaporate. Note: If not used immediately, the cultureware must be sealed to prevent evaporation of the Corning Matrigel solution (e.g. with Parafilm ) and can be stored at 2-8 C for up to 7 days after coating. Allow stored coated cultureware to come to room temperature (15-25 C) for 30 minutes before plating cells. 4.2 AggreWell 800 plates The following are instructions for preparing one well of an AggreWell 800 plate. If using more wells, adjust volumes accordingly. 1. Add Y-27632 (Dihydrochloride) to STEMdiff Neural Induction Medium to obtain a final concentration of 10 µm (STEMdiff Neural Induction Medium + 10 µm Y-27632). 2. Warm (37 C) sufficient DMEM/F-12 and STEMdiff Neural Induction Medium + 10 µm Y-27632. 3. Wash each well with 1 ml of DMEM/F-12. 4. Aspirate and add 1 ml of STEMdiff Neural Induction Medium + 10 µm ROCK inhibitor. Note: The AggreWell 800 plate contains eight wells with microwells. Ensure the medium is placed in wells containing microwells. Do not use empty wells for EB formation. 5. Centrifuge the AggreWell 800 plate at 2000 x g for 5 minutes. Note: Plates must be balanced. It is recommended to balance the plate against a standard 24-well plate filled with water to match the weight and position of the AggreWell 800 plate. 6. Examine the plate under a microscope to ensure that all bubbles have been removed. Note: If bubbles remain trapped in the microwells, centrifuge again at a higher speed (e.g. 3000 x g) for an additional 5 minutes. 7. Set the AggreWell 800 plate aside until use. Note: Do not remove medium at time of use.

7 5.0 Neural Induction: Generating NPCs from Human ES and ips Cells STEMdiff Neural Induction Medium can be used to generate CNS-type NPCs from human ES and ips cells using either EB (Figure 1A; section 5.1) or monolayer culture (Figure 1B; section 5.2) protocols. Some of the key differences between these two protocols are outlined in Table 3. Generated NPCs can then be immunocytochemically characterized using the STEMdiff Human Neural Progenitor Antibody Panel, which includes primary antibodies that are immunoreactive towards marker proteins highly expressed either by NPCs (Nestin, PAX6, SOX1) or by undifferentiated human ES and ips cells (OCT4/OCT3). Refer to Document #28137 for complete instructions on using this antibody panel. Figure 1. Schematic of the Embryoid Body and Monolayer Culture Protocols. For NPC culture using STEMdiff Neural Progenitor Medium, refer to section 6.0.

8 Table 3. Comparison of Embryoid Body and Monolayer Culture Protocols NEURAL INDUCTION PROTOCOL EMBRYOID BODY MONOLAYER CULTURE DAYS TO SINGLE CELL NPCs 16-19 6-9 METHOD TO CONFIRM NEURAL INDUCTION Visual inspection or phenotypic characterization Phenotypic characterization only NEURAL ROSETTE SELECTION Yes No hpsc FEEDER-FREE MAINTENANCE MEDIUM COMPATIBILITY mtesr 1 mtesr 1 or TeSR -E8 5.1 EB Protocol Day 0: Generating EB using AggreWell 800 The following instructions are for generating a single-cell suspension of human ES and ips cells previously cultured in mtesr 1 in a 100 mm dish and then plating cells into one well of an AggreWell 800 plate. If using other cultureware or number of wells, adjust volumes accordingly. 3 x 10 6 cells will be required for each well of an AggreWell 800, resulting in 10,000 cells per microwell. Note: Addition of Y-27632 (Dihydrochloride) to STEMdiff Neural Induction Medium is only required on Day 0. 1. Prepare a well in an AggreWell 800 plate (section 4.2). 2. Add Y-27632 (Dihydrochloride) to STEMdiff Neural Induction Medium to obtain a final concentration of 10 µm (STEMdiff Neural Induction Medium + 10 µm Y-27632). 3. Warm (37 C) sufficient volumes of STEMdiff Neural Induction Medium + 10 µm Y-27632, Gentle Cell Dissociation Reagent, PBS (without Ca 2+ and Mg 2+ ), and DMEM/F-12. 4. Use a microscope to visually identify regions of differentiation in the human ES and ips cell culture. Mark these using a felt tip or lens marker on the bottom of the 100 mm dish. Remove regions of differentiation by scraping with a pipette tip or by aspiration. 5. Wash the dish once with 5-10 ml of sterile PBS. 6. Aspirate and add 3 ml of Gentle Cell Dissociation Reagent 7. Incubate at 37 C for 8-10 minutes. Note: The incubation time may vary when using different cell lines or other non-enzymatic cell dissociation reagents, therefore dissociation should be monitored under the microscope until the optimal time is determined. 8. Dislodge cells by pipetting up and down 3-5 times using a micropipette. Collect the cells into a 15 or 50 ml tube using a 5 ml serological pipette and ensure that any remaining cell aggregates are broken up into single cells. 9. Wash the dish with 10 ml of DMEM/F-12 and add to the tube containing the single-cell suspension. 10. Count viable cells using Trypan Blue and a hemacytometer. 11. Centrifuge at 300 x g for 5-10 minutes. 12. Carefully aspirate the supernatant and resuspend cells in STEMdiff Neural Induction Medium + 10 µm Y-27632 to obtain a final concentration of 3 x 10 6 cells/ml. 13. Add 1 ml of the single-cell suspension (i.e. 3 x 10 6 cells) to a single well of the AggreWell 800 plate. This will result in 10,000 cells/microwell.

9 Note: Ensure that newly plated cells are evenly dispersed across the entire surface of the well by gently pipetting up and down several times. 14. Centrifuge the AggreWell 800 plate at 100 x g for 3 minutes. This will capture the cells in the microwells. Note: Plates must be balanced. It is recommended to balance the plate against a standard 24-well plate filled with water to match the weight and position of the AggreWell 800 plate. 15. Examine the AggreWell 800 plate under a microscope to ensure that cells are evenly distributed among the microwells. 16. Incubate cells at 37 C. Days 1-4: Partial Medium Change Note: On Day 1, uniform EBs should be visible in the AggreWell 800 well. At least 50% of cells within the microwell should be incorporated into the EBs. See section 7.0 for troubleshooting suggestions. Perform daily partial (3/4) medium change using the following protocol on Days 1-4. The following instructions are for performing a partial medium change in a single well of an AggreWell 800 plate. 1. Warm (37 C) sufficient volumes of STEMdiff Neural Induction Medium. 2. Carefully remove the AggreWell 800 plate from the incubator, taking care not to rock or shake the contents. 3. Gently remove 1.5 ml of the medium from the well using a 1 ml micropipette (e.g. P-1000) and discard. Note: Do not disturb the EBs. Keep the pipette tip towards the upper surface of the medium in the well while removing the medium. 4. Slowly add 1.5 ml of STEMdiff Neural Induction Medium into the well using a 1 ml micropipette. Note: It is important not to disturb the EBs. Do NOT add the medium directly onto the surface of the well. Support the pipette tip by slightly touching the side of the AggreWell 800 well at the surface level of the remaining medium inside the well. This will allow for a more controlled release of the medium. 5. Incubate at 37 C. 6. Repeat steps 1-5 until Day 4. Day 5: Replating EBs On Day 5, EBs should be harvested from AggreWell 800 wells and plated onto matrix-coated cultureware. The following instructions are for harvesting EBs from a single well of an AggreWell 800 plate and replating them on a matrix-coated single well of a 6-well plate. If using multiple wells or other cultureware, adjust volumes accordingly. 1. Coat a well of a new 6-well plate with either PLO/L (section 4.1.1) or Corning Matrigel (section 4.1.2). 2. Warm (37 C) sufficient volumes of DMEM/F-12 and STEMdiff Neural Induction Medium. 3. Place a 37 µm reversible strainer on top of a 50 ml tube. Label the tube waste. Note: The arrow on the reversible strainer should point upwards. Use a new strainer and a new tube for each AggreWell 800 well to be harvested. 4. Remove the medium and firmly expel it into the well using a 1 ml micropipette with a standard disposable tip. This will dislodge the EBs from the AggreWell 800 well. 5. Switch to a large bore tip and filter the EB suspension through the 37 µm reversible strainer. EBs will remain on top of the strainer and single cells will flow through into the waste tube.

10 6. Take 1 ml of DMEM/F-12 using a micropipette and firmly expel it into the same AggreWell 800 well. While EBs are in suspension, quickly switch to a large bore tip to transfer the EB suspension into the same strainer as in step 5. 7. Repeat step 6 until all EBs have been removed. Examine the well under a microscope to ensure that all EBs have been removed. 8. Invert the strainer over a new 50 ml conical tube and add 2 ml of STEMdiff Neural Induction Medium onto the strainer to collect all the EBs. 9. Gently remove the matrix solution from the new plate using a serological pipette or by aspiration. Ensure that the coated surface is not scratched. 10. Plate the EB suspension (from step 8) into a single well of the matrix-coated 6-well plate using a large bore tip or a serological pipette. This will avoid breaking up the EBs. 11. Place the 6-well plate in a 37 C incubator. Move the 6-well plate in several quick, short, back-and-forth and side-to-side motions to distribute the EBs across the surface of the wells. Days 6-11: Medium Change Perform a daily full medium change with warm (37 C) STEMdiff Neural Induction Medium. Use 2 ml/well of medium for a 6-well plate. If using other cultureware, adjust volumes accordingly. On Day 7, examine the morphology of your culture and estimate the percentage of neural induction per well. EBs will have spread out and neural rosettes should be clearly visible. Use the following protocol to calculate neural induction. Note: If neural induction calculated on Day 7 is < 75%, neural rosette selection may be inefficient. Refer to section 7.0 for troubleshooting suggestions. 1. Count all attached EBs. 2. Count attached EBs in which 50% or more of the area of each individual aggregate is filled with neural rosettes. See Figure 2A for a representative image of EBs with 100% neural rosettes and Figure 2B for a representative image of EBs with less than 50% neural rosettes. 3. Quantify neural rosette induction using the following formula: % = # % # Figure 2. Assessing Neural Induction by Scoring Neural Rosettes Formation in EBs on Day 7. Neural induction was calculated to be (A) 100% and (B) 39.2%.

11 Day 12: Neural Rosette Selection and Replating The following instructions are for selecting neural rosettes from a single well of a 6-well plate and plating them onto a new matrix-coated well of a new 6-well plate. If using other cultureware or number of wells, adjust volumes accordingly. 1. Coat a well of a new 6-well plate with either PLO/L (section 4.1.1) or Corning Matrigel (section 4.1.2). 2. Warm (37 C) sufficient volumes of STEMdiff Neural Rosette Selection Reagent, STEMdiff Neural Induction Medium and DMEM/F-12. 3. Aspirate medium from the well and add 1 ml of DMEM/F-12. 4. Aspirate medium and add 1 ml of STEMdiff Neural Rosette Selection Reagent. 5. Incubate at 37 C for 1 hour. Note: This incubation time may need to be optimized. Refer to section 7.0 for troubleshooting suggestions. 6. Carefully remove and discard the STEMdiff Neural Rosette Selection Reagent using a micropipette. 7. Add 1 ml of DMEM/F12 and firmly expel it back into the well using a 1 ml micropipette with a standard disposable tip, aiming specifically at the rosette clusters. This will dislodge the neural rosettes from the well. 8. Collect the neural rosette suspension in a 15 ml tube. Do not further resuspend the neural rosette suspension. 9. Repeat steps 6 and 7 until the majority of the neural rosette clusters have been collected when examined under a microscope. See Figure 3 for representative examples. Note: If the majority of neural rosettes have not detached, refer to section 7.0 for troubleshooting suggestions. Note: To avoid contamination with non-cns-type cells, do not over-select. It is preferable to leave some rosettes behind, slightly sacrificing yield for higher purity. 10. Centrifuge at 350 x g for 5 minutes. 11. Carefully aspirate the supernatant and add 2 ml of STEMdiff Neural Induction Medium. Gently resuspend the neural rosettes by pipetting slowly up and down 1-2 times using a 1 ml micropipette. Note: The suspension should contain large neural rosette clusters. Do not create a single-cell suspension. 12. Gently remove the matrix solution from the new plate using a serological pipette or by aspiration. Ensure that the coated surface is not scratched. 13. Plate the neural rosette suspension (2 ml) onto a single well of the matrix-coated 6-well plate. 14. Place the 6-well plate in a 37 C incubator. Move the 6-well plate in several quick, short, back-and-forth and side-to-side motions to distribute the neural rosettes across the surface of the wells.

12 Figure 3. Selective Detachment of Neural Rosettes Using STEMdiff Neural Rosette Selection Reagent. Examples of neural rosettes (A) before and (B) after incubation with STEMdiff Neural Rosette Selection Reagent. (C) After selection, all neural rosettes have been removed. Days 13-17 (or 19): Medium Change Perform a daily full medium change with warm (37 C) STEMdiff Neural Induction Medium until cultures are ready to be passaged. Use 2 ml/well of a 6-well plate. If using other cultureware, adjust volumes accordingly. Selected rosette-containing clusters will attach and NPC outgrowths will form a monolayer between the clusters. NPCs are ready for passage 1 when cultures are approximately 80-90% confluent (typically at about Day 17-19; see Figure 4A for a representative image). See section 6.0 for detailed instructions on how to passage and maintain NPCs using STEMdiff Neural Progenitor Medium. Note: On Day 13, high levels of cell death are typically observed. This does not affect the final yield of NPCs. NPCs will eventually start filling the gaps between larger rosette-containing clusters within 2-5 days.

13 5.2 Monolayer Culture Protocol Day 0: Plating Single Cells The following instructions are for generating CNS-type NPCs from human ES and ips cells previously cultured in mtesr 1 or TeSR -E8 in a 100 mm dish, and then plated into a single well of a 6-well plate. If using other cultureware or number of wells, adjust volumes accordingly. Note: Addition of Y-27632 (Dihydrochloride) to STEMdiff Neural Induction Medium is only required on Day 0. 1. Coat a well of a new 6-well plate with either PLO/L (section 4.1.1) or Corning Matrigel (section 4.1.2). 2. Add Y-27632 (Dihydrochloride) to STEMdiff Neural Induction Medium to obtain a final concentration of 10 µm (STEMdiff Neural Induction Medium + 10 µm Y-27632). 3. Warm (37 C) sufficient volumes of STEMdiff Neural Induction Medium + 10 µm Y-27632, Gentle Cell Dissociation Reagent, PBS (without Ca 2+ and Mg 2+ ), and DMEM/F-12. 4. Use a microscope to visually identify regions of differentiation in the human ES and ips cell culture. Mark these using a felt tip or lens marker on the bottom of the 100 mm dish. Remove regions of differentiation by scraping with a pipette tip or by aspiration. 5. Wash the dish once with 5-10 ml of sterile PBS. 6. Aspirate and add 3 ml of Gentle Cell Dissociation Reagent 7. Incubate at 37 C for 8-10 minutes. Note: The incubation time may vary when using different cell lines or other non-enzymatic cell dissociation reagents, therefore dissociation should be monitored under the microscope until the optimal time is determined. 8. Dislodge cells by pipetting up and down 3-5 times using a micropipette. Collect the cells into a 15 or 50 ml tube using a 5 ml serological pipette and ensure that any remaining cell aggregates are broken up into single cells. 9. Wash the dish with 10 ml of DMEM/F-12 and add to the tube containing the single-cell suspension. 10. Count viable cells using Trypan Blue and a hemacytometer. 11. Centrifuge cells at 300 x g for 5-10 minutes. 12. Carefully aspirate the supernatant and resuspend cells in STEMdiff Neural Induction Medium + 10 µm Y-27632 to obtain a final concentration of 1 x 10 6 cells/ml (i.e. 2 x 10 5 cells/cm 2 ). Note: Plating densities of 2-2.5 x 10 5 cells/cm 2 are recommended. 13. Gently remove the matrix solution from the new plate using a serological pipette or by aspiration. Ensure that the coated surface is not scratched. 14. Plate 2 ml of cell suspension (2 x 10 6 cells/well) onto a single well of the matrix-coated 6-well plate. 15. Place the 6-well plate in a 37 C incubator. Move the 6-well plate in several quick, short, back-and-forth and side-to-side motions to distribute the neural rosettes across the surface of the wells. Days 1-6 (or 9): Medium Change Perform a daily full medium change with warm (37 C) STEMdiff Neural Induction Medium until cultures are ready to be passaged (i.e. when cells are approximately 80-90% confluent, typically after approximately 7 days of culture). Use 2 ml/well of a 6-well plate. Note: Addition of Y-27632 (Dihydrochloride) to STEMdiff Neural Induction Medium is not required when performing daily medium changes.

14 Day 6-9: Passage Cells NPCs are ready for passage 1 when cultures are approximately 80-90% confluent (typically Day 6-9). The following are instructions for passaging cells from one well of a 6-well plate and plating them onto a new matrix-coated well of a new 6-well plate. If using other cultureware, adjust volumes accordingly. 1. Coat a well of a new 6-well plate with either PLO/L (section 4.1.1) or Corning Matrigel (section 4.1.2). 2. Add Y-27632 (Dihydrochloride) to STEMdiff Neural Induction Medium to obtain a final concentration of 10 µm (STEMdiff Neural Induction Medium + 10 µm Y-27632). 3. Warm (37 C) sufficient volumes of STEMdiff Neural Induction Medium + 10 µm Y-27632, DMEM/F-12, and ACCUTASE. Optional: Wash cells to be passaged with 1 ml of DMEM/F-12. 4. Aspirate medium and add 1 ml of ACCUTASE. 5. Incubate at 37 C for 5-10 minutes. 6. Dislodge remaining attached cells by pipetting up and down using a 1 ml micropipette. 7. Add 5 ml of DMEM/F-12 and transfer the NPC-suspension to a 15 ml tube. 8. Centrifuge at 300 x g for 5 minutes. 9. Carefully aspirate the supernatant and add 1 ml of complete STEMdiff Neural Induction Medium + 10 µm Y-27632. 10. Count viable cells using Trypan Blue and a hemacytometer. 11. Gently remove the matrix solution from the new plate using a serological pipette or by aspiration. Ensure that the coated surface is not scratched. 12. Plate cells at desired density (e.g. 1.5-2 x 10 5 cells/cm 2 ) in 2 ml of STEMdiff Neural Induction Medium onto matrix-coated cultureware. 13. Place the 6-well plate in a 37 C incubator. Move the 6-well plate in several quick, short, back-and-forth and side-to-side motions to distribute the NPCs across the surface of the wells. 14. Perform daily medium change using STEMdiff Neural Induction Medium. Note: Addition of Y-27632 (Dihydrochloride) to STEMdiff Neural Induction Medium is not required when performing daily medium changes. 15. Visually assess cultures to monitor growth and to determine timing of the next passage (i.e. when cells are approximately 80-90% confluent, typically after approximately 5-7 days of culture). Note: It is recommended to passage NPCs using the above protocol one more time. When NPCs are ready for passage 3, continue to section 6.0 using STEMdiff Neural Progenitor Medium.

15 6.0 Neural Progenitor Cell Culture STEMdiff Neural Progenitor Medium is optimized for the expansion of NPCs generated using STEMdiff Neural Induction Medium using either the EB protocol (section 5.1) or the monolayer culture protocol (section 5.2). NPCs cultured in STEMdiff Neural Progenitor Medium display typical NPC morphology and express markers that are indicative of CNS-type NPCs, such as PAX6 and SOX1. These markers can be characterized using the STEMdiff Human Neural Progenitor Antibody Panel. In addition, NPCs generated using STEMdiff Neural Induction Medium or expanded using STEMdiff Neural Progenitor Medium can be cryopreserved using STEMdiff Neural Progenitor Freezing Medium (section 6.3). Figure 4. Confluent NPC Cultures Ready to be Passaged using STEMdiff Neural Progenitor Medium. Examples of NPCs obtained after the (A) EB protocol (section 5.1) and (B) the monolayer culture protocol (section 5.2). Cells should be approximately 80-90% confluent before passaging. 6.1 Complete STEMdiff Neural Progenitor Medium Use sterile techniques to prepare complete STEMdiff Neural Progenitor Medium (Basal Medium [#05834] + Supplement A [#05836] + Supplement B [#05837]). The following example is for preparing approximately 100 ml of complete STEMdiff Neural Progenitor Medium. If preparing other volumes, adjust accordingly. 1. Thaw STEMdiff Neural Progenitor Basal Medium at room temperature (15-25 C) or overnight at 2-8 C. Note: Once thawed, use immediately or store at 2-8 C for up to 3 weeks. Alternatively, aliquot and store at -20 C. Do not exceed the shelf life of the basal medium. After thawing the aliquoted basal medium, use immediately. Do not re-freeze. 2. Thaw STEMdiff Neural Progenitor Supplement A (50X) and Supplement B (1000X) at room temperature (15-25 C) or at 2-8 C.. Note: Once thawed, use immediately or aliquot and store at -20 C. Do not exceed the shelf life of the supplements. After thawing the aliquoted supplements, use immediately. Do not re-freeze. 3. Add 2 ml of the STEMdiff Neural Progenitor Supplement A and 100 µl of the STEMdiff Neural Progenitor Supplement B to 98 ml of the STEMdiff Neural Progenitor Basal Medium. Mix well. Note: If not used immediately, store complete STEMdiff Neural Progenitor Medium at 2-8 C for 2 weeks. Do not freeze complete medium.

16 6.2 Passaging Protocol NPCs are ready for passage when cultures are approximately 80-90% confluent (see Figure 4). Note: For monolayer neural induction passage 1 and 2, follow passaging procedures in section 4.1. The following are instructions for passaging cells from one well of a 6-well plate and plating them onto a new matrix-coated well of a new 6-well plate. If using other cultureware, adjust volumes accordingly. 1. Coat a well of a new 6-well plate with either PLO/L (section 4.1.1) or Corning Matrigel (section 4.1.2). 2. Warm (37 C) sufficient volumes of complete STEMdiff Neural Progenitor Medium (section 6.1), DMEM/F-12, and ACCUTASE. Optional: Wash cells to be passaged with 1 ml of DMEM/F-12. 3. Aspirate medium and add 1 ml of ACCUTASE. 4. Incubate at 37 C for 5-10 minutes. 5. Dislodge remaining attached cells by pipetting up and down using a 1 ml micropipette. 6. Add 5 ml of DMEM/F-12 and transfer the NPC-suspension to a 15 ml tube. 7. Centrifuge at 300 x g for 5 minutes. 8. Carefully aspirate the supernatant and add 1 ml of complete STEMdiff Neural Progenitor Medium. 9. Count viable cells using Trypan Blue and a hemacytometer. 10. Gently remove the matrix solution using a serological pipette or by aspiration. Ensure that the coated surface is not scratched. 11. Plate cells at desired density (e.g. 1.25 x 10 5 cells/cm 2 ) in 2 ml of complete STEMdiff Neural Progenitor Medium onto matrix-coated cultureware. 12. Place the 6-well plate in a 37 C incubator. Move the 6-well plate in several quick, short, back-and-forth and side-to-side motions to distribute the NPCs across the surface of the wells. 13. Perform daily medium change using complete STEMdiff Neural Progenitor Medium. 14. Visually assess cultures to monitor growth and to determine timing of the next passage (i.e. when cells are approximately 80-90% confluent, typically after approximately 7 days of culture). 6.3 Freezing Protocol 1. Prepare a single-cell suspension of NPCs using a passaging protocol of your choice. For example, follow instructions in section 6.2 until step 6. 2. Count viable cells using Trypan Blue and a hemacytometer. 3. Centrifuge cells at 300 x g for 5 minutes. 4. Carefully aspirate the supernatant and resuspend cell pellet at 2-4 x 10 6 cells/ml using cold (2-8 C) STEMdiff Neural Progenitor Freezing Medium. 5. Transfer 1 ml of cell-suspension into each cryovial. 6. Freeze cells using a standard slow rate-controlled cooling protocol that reduces temperatures at a rate of approximately -1 C/min, followed by long-term storage at -135 C (liquid nitrogen) or colder. Long-term storage at -80 C is not recommended.

17 6.4 Thawing Protocol In general, one frozen vial containing 2-4 x 10 6 NPCs can be successfully thawed into one well of a 6-well plate. 1. Coat a well of a new 6-well plate with either PLO/L (section 4.1.1) or Corning Matrigel (section 4.1.2). 2. Warm (37 C) DMEM/F-12 and medium (e.g. complete STEMdiff Neural Progenitor Medium) before starting the protocol to ensure that the thawing procedure is done as quickly as possible. 3. Add 10 ml of warm DMEM/F-12 to a 15 ml tube. 4. Quickly thaw cells in a 37 C water bath by gently shaking the cryovial continuously until only a small frozen cell pellet remains. 5. Remove the cryovial from the water bath and wipe it with 70% ethanol or isopropanol. 6. Transfer cells from the cryovial to the 15 ml tube containing DMEM/F-12. Mix gently. 7. Centrifuge cells at 300 x g for 5 minutes. 8. Aspirate medium, leaving the cell pellet intact. Gently resuspend the cell pellet in 2 ml of medium (e.g. complete STEMdiff Neural Progenitor Medium). 9. Gently remove the matrix solution from the new plate using a serological pipette or by aspiration. Ensure that the coated surface is not scratched. 10. Plate cells onto 1 well of a matrix-coated 6-well plate. 11. Place the 6-well plate in a 37 C incubator. Move the 6-well plate in several quick, short, back-and-forth and side-to-side motions to distribute the NPCs across the surface of the wells.

18 7.0 Troubleshooting 7.1 Generating NPCs Using the EB Protocol PROBLEM Air bubbles are present in microwells of the AggreWell 800 plate prior to adding hpscs. Uneven distribution of hpscs into all microwells. hpscs overflow microwell capacity. Poor incorporation of hpscs into EBs. Poor survival of hpscs on Day 1. Difficulty removing EBs from microwells of the AggreWell 800 plate. EBs break up when removing from microwells. EBs do not attach on Day 6. Neural induction is < 75%. Poor survival of cells within neural rosettes. Excessive cell death occurs after lifting and re-plating neural rosettes using STEMdiff Neural Rosette Selection Reagent (after Day 12). Difficulty isolating neural rosettes. SOLUTION Ensure that the AggreWell 800 plate was prepared prior to use, as described in section 4.2. Immediately after adding the hpsc suspension, pipette several times with a micropipette and 1 ml pipette tip, to generate an evenly distributed cell suspension. Do not exceed 20,000 cells per microwell. The recommended number of cells per microwell is 10,000. Ensure that high quality hpscs are used when starting the protocol. Ensure that Y-27632 (Dihydrochloride) has been added at a final concentration of 10 µm when plating the single-cell suspension of hpscs into the AggreWell 800 plate. If issues persist, pre-coat the microwells with AggreWell Rinsing Solution (Catalog #07010) on Day 0 prior to preparing the AggreWell 800 plate: 1. Add 1 ml of the AggreWell Rinsing Solution per well of an AggreWell 800 plate. 2. Centrifuge at 2000 x g for 5 minutes to remove any small bubbles. 3. Incubate at room temperature (15-25 C) for 30 minutes. 4. Remove the AggreWell Rinsing Solution and wash with DMEM/F-12 prior to use. Ensure that a large bore tip is used instead of a regular 1 ml micropipette tip when dislodging and transferring the EBs. Ensure that high quality hpscs are used when starting the protocol. Ensure that the cultureware is coated with appropriate matrix (section 4.1) prior to plating the EBs on Day 5. Ensure that high quality hpscs are used when starting the protocol. Perform daily medium changes with STEMdiff Neural Induction Medium. Ensure that high quality hpscs are used when starting the protocol. If issues persist: 1. Culture EBs for a longer time period in AggreWell 800 plates e.g. 7 days instead of 5 days. 2. Isolate neural rosettes using STEMdiff Neural Rosette Selection Reagent at an earlier time point e.g. Day 10 or 11 instead of Day 12. Cell death is to be expected after the treatment with STEMdiff Neural Rosette Selection Reagent due to low survival of single cell NPCs. Single cell NPCs should fill in the gaps between larger clumps after a few days and re-from rosettes. It is crucial to NOT break up neural rosettes into single cells. Ensure that neural rosettes are plated at a high density. On Day 12, add STEMdiff Neural Rosette Selection Reagent to the well and incubate at 37 C for another 20-30 minutes.

19 PROBLEM Poor differentiation of NPCs and/or detection of non-cns type NPCs. SOLUTION When using STEMdiff Neural Rosette Selection Reagent on Day 12, isolate the neural rosettes and avoid collecting surrounding cells. Ensure that high quality hpscs are used when starting the protocol. If issues persist: 1. Culture EBs for a longer time period in AggreWell 800 plates e.g. 7 days instead of 5 days. 2. Isolate neural rosettes using STEMdiff Neural Rosette Selection Reagent at an earlier time point e.g. Day 10 or 11 instead of Day 12. 7.2 Generating NPCs Using the Monolayer Culture Protocol PROBLEM hpscs are confluent on Day 1. No neural rosettes are visible. Neural induction is not complete by Day 6 in the monolayer protocol or Day 7 of the EB protocol. Cell death is observed when single cell suspension of hpscs are plated. Low attachment or cell death after passage 1. SOLUTION Check cell count prior to plating hpscs on Day 0. Decrease plating density of hpscs on Day 0. Typically neural rosettes are not observed due to high cell density. For assessment of neural induction, characterize expression of markers such as PAX6 (e.g. using STEMdiff Human Neural Progenitor Antibody Panel). Timing of neural induction may need to be optimized for individual hpscs. It is normal to observe cell death on Day 1-3 of the monolayer protocol. Remaining attached cells will proliferate to confluency by Day 6-9. Ensure that 10 µm Y-27632 (Dihydrochloride) is added when passaging NPCs using STEMdiff Neural Induction Medium on Day 6-9.

20 8.0 References 1. Itskovitz-Eldor J, et al. Differentiation of human embryonic stem cells into embryoid bodies compromising the three embryonic germ layers. Mol Med 6(2): 88-95, 2000 2. Watanabe K, et al. A ROCK Inhibitor Permits Survival of Dissociated Human Embryonic Stem Cells. Nat Biotechnol 25(6): 681-6, 2007 Copyright 2014 by STEMCELL Technologies Inc. All rights reserved including graphics and images. STEMCELL Technologies & Design, STEMCELL Shield Design, Scientists Helping Scientists, STEMdiff, are trademarks of STEMCELL Technologies Inc. Matrigel is a trademark of Corning Incorporated. E8, mtesr and TeSR are trademarks of WARF. Parafilm is a registered trademark of Bemis Company, Inc. All other trademarks are the property of their respective holders. While STEMCELL has made all reasonable efforts to ensure that the information provided by STEMCELL and its suppliers is correct, it makes no warranties or representations as to the accuracy or completeness of such information. TOLL FREE PHONE 1 800 667 0322 PHONE +1 604 877 0713 VERSION 2.0.0

Scientists Helping Scientists T M WWW.STEMCELL.COM TOLL FREE PHONE 1 800 667 0322 PHONE +1 604 877 0713 INFO@STEMCELL.COM TECHSUPPORT@STEMCELL.COM FOR GLOBAL CONTACT DETAILS VISIT OUR WEBSITE DOCUMENT #28782 VERSION 2.1.0